Cell Reception Decline

My family and I were gone for a week and when we came back our cell service is very poor.  Calls are dropping and cutting in and out.  We used to have 4/4 bars of service in and around our home and now I rarely get more than 2/4. Our neighbors use Verizon and have not had the same issue.  We will switch as well if service doesn't improve as I do a lot of work from home and need reliable, clear phone reception.  Our zip code is 47639.